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                <ol class="chapter"><li class="chapter-item affix "><a href="../../index.html">Andrew's Blog</a></li><li class="chapter-item "><a href="../../posts/linux/linux.html"><strong aria-hidden="true">1.</strong> Linux</a><a class="toggle"><div>❱</div></a></li><li><ol class="section"><li class="chapter-item "><a href="../../posts/linux/install_linux.html"><strong aria-hidden="true">1.1.</strong> install linux</a></li><li class="chapter-item "><a href="../../posts/linux/bash_profile.html"><strong aria-hidden="true">1.2.</strong> bash profile</a></li><li class="chapter-item "><a href="../../posts/linux/command_list.html"><strong aria-hidden="true">1.3.</strong> command list</a></li><li class="chapter-item "><a href="../../posts/linux/git_guide.html"><strong aria-hidden="true">1.4.</strong> git guide</a></li><li class="chapter-item "><a href="../../posts/linux/tar.html"><strong aria-hidden="true">1.5.</strong> tar</a></li><li class="chapter-item "><a href="../../posts/Linux/git_cheatsheet.html"><strong aria-hidden="true">1.6.</strong> Git Cheatsheet</a></li><li class="chapter-item "><a href="../../posts/Linux/bash_cheatsheet.html"><strong aria-hidden="true">1.7.</strong> Bash Cheatsheet</a></li></ol></li><li class="chapter-item "><a href="../../posts/macos/mac.html"><strong aria-hidden="true">2.</strong> MacOS</a><a class="toggle"><div>❱</div></a></li><li><ol class="section"><li class="chapter-item "><a href="../../posts/macos/macos_profiles.html"><strong aria-hidden="true">2.1.</strong> macos profiles</a></li><li class="chapter-item "><a href="../../posts/macos/macos_pwn_env_setup.html"><strong aria-hidden="true">2.2.</strong> macos pwn env setup</a></li></ol></li><li class="chapter-item "><a href="../../posts/swift/swift.html"><strong aria-hidden="true">3.</strong> Swift</a><a class="toggle"><div>❱</div></a></li><li><ol class="section"><li class="chapter-item "><a href="../../posts/swift/learn_swift.html"><strong aria-hidden="true">3.1.</strong> learn swift basics</a></li><li class="chapter-item "><a href="../../posts/swift/swift_extensions.html"><strong aria-hidden="true">3.2.</strong> Swift extensions</a></li><li class="chapter-item "><a href="../../posts/swift/swiftui_extension.html"><strong aria-hidden="true">3.3.</strong> SwiftUI extensions</a></li><li class="chapter-item "><a href="../../posts/swift/install_swift.html"><strong aria-hidden="true">3.4.</strong> install swift</a></li><li class="chapter-item "><a href="../../posts/swift/task_planner.html"><strong aria-hidden="true">3.5.</strong> implment task panner app with SwiftUI</a></li><li class="chapter-item "><a href="../../posts/swift/swift_cheat_sheet.html"><strong aria-hidden="true">3.6.</strong> Swift Cheat Sheet</a></li><li class="chapter-item "><a href="../../posts/swift/yinci_url.html"><strong aria-hidden="true">3.7.</strong> Personal privacy protocol</a></li><li class="chapter-item "><a href="../../posts/swift/swift_regular_exressions.html"><strong aria-hidden="true">3.8.</strong> Swift regular exressions</a></li><li class="chapter-item "><a href="../../posts/ios/how_to_create_beautiful_ios_charts_in_swift.html"><strong aria-hidden="true">3.9.</strong> How to Create Beautiful iOS Charts in Swift</a></li><li class="chapter-item "><a href="../../posts/swift/swiftui_source_code.html"><strong aria-hidden="true">3.10.</strong> SwiftUI source code</a></li><li class="chapter-item "><a href="../../posts/swift/use_swift_fetch_iciba_api.html"><strong aria-hidden="true">3.11.</strong> use swift fetch iciba API</a></li></ol></li><li class="chapter-item "><a href="../../posts/ios/ios.html"><strong aria-hidden="true">4.</strong> iOS</a><a class="toggle"><div>❱</div></a></li><li><ol class="section"><li class="chapter-item "><a href="../../posts/ios/cocaposd_setup_and_install_for_ios_project.html"><strong aria-hidden="true">4.1.</strong> cocaposd setup and install for ios project</a></li><li class="chapter-item "><a href="../../posts/ios/swiftui_show_gif_image.html"><strong aria-hidden="true">4.2.</strong> SwiftUI show gif image</a></li><li class="chapter-item "><a href="../../posts/ios/implement_task_planner_app.html"><strong aria-hidden="true">4.3.</strong> implement Task planner App</a></li></ol></li><li class="chapter-item "><a href="../../posts/objective_c/objective_c.html"><strong aria-hidden="true">5.</strong> Objective-C</a><a class="toggle"><div>❱</div></a></li><li><ol class="section"><li class="chapter-item "><a href="../../posts/objective_c/objective_c_cheat_sheet.html"><strong aria-hidden="true">5.1.</strong> Objective-C Cheat Sheet</a></li><li class="chapter-item "><a href="../../posts/objective_c/objective_c_for_absolute_beginners_read_note.html"><strong aria-hidden="true">5.2.</strong> Objective-C Note</a></li></ol></li><li class="chapter-item "><a href="../../posts/dart/dart.html"><strong aria-hidden="true">6.</strong> Dart</a><a class="toggle"><div>❱</div></a></li><li><ol class="section"><li class="chapter-item "><a href="../../posts/dart/flutter.html"><strong aria-hidden="true">6.1.</strong> Flutter Cheat Sheet</a></li><li class="chapter-item "><a href="../../posts/dart/dart_cheat_sheet.html"><strong aria-hidden="true">6.2.</strong> Dart Cheat Sheet</a></li><li class="chapter-item "><a href="../../posts/flutter/flutter_dev_test.html"><strong aria-hidden="true">6.3.</strong> Flutter dev test</a></li></ol></li><li class="chapter-item "><a href="../../posts/rust/rust.html"><strong aria-hidden="true">7.</strong> Rust</a><a class="toggle"><div>❱</div></a></li><li><ol class="section"><li class="chapter-item "><a href="../../posts/rust/offline_use_rust.html"><strong aria-hidden="true">7.1.</strong> Offline use rust</a></li><li class="chapter-item "><a href="../../posts/rust/rust_grammer.html"><strong aria-hidden="true">7.2.</strong> rust grammar</a></li><li class="chapter-item "><a href="../../posts/rust/pase_string_and_decimal_conversion.html"><strong aria-hidden="true">7.3.</strong> pase string and decimal conversion</a></li><li class="chapter-item "><a href="../../posts/rust/parse_types.html"><strong aria-hidden="true">7.4.</strong> rust types</a></li><li class="chapter-item "><a href="../../posts/rust/rust_life_cycle.html"><strong aria-hidden="true">7.5.</strong> Rust life cycle</a></li><li class="chapter-item "><a href="../../posts/rust/rust_generic.html"><strong aria-hidden="true">7.6.</strong> rust generics</a></li><li class="chapter-item "><a href="../../posts/rust/rust_implment_matrix.html"><strong aria-hidden="true">7.7.</strong> Rust implement matrix</a></li><li class="chapter-item "><a href="../../posts/rust/rust_sort.html"><strong aria-hidden="true">7.8.</strong> Rust implement sort algorithms</a></li><li class="chapter-item "><a href="../../posts/rust/implement_aes_encryption.html"><strong aria-hidden="true">7.9.</strong> Rust implement AEC encryption and decryption</a></li><li class="chapter-item "><a href="../../posts/rust/implement_trie_data_structure.html"><strong aria-hidden="true">7.10.</strong> implement trie data structure</a></li><li class="chapter-item "><a href="../../posts/rust/rust_implement_tree.html"><strong aria-hidden="true">7.11.</strong> implement tree data_structure</a></li><li class="chapter-item "><a href="../../posts/rust/list_dir.html"><strong aria-hidden="true">7.12.</strong> list dir</a></li><li class="chapter-item "><a href="../../posts/rust/fast_way_to_implment_object_trait.html"><strong aria-hidden="true">7.13.</strong> fast way to implment object trait</a></li><li class="chapter-item "><a href="../../posts/rust/compress_rust_binary_size.html"><strong aria-hidden="true">7.14.</strong> compress rust binary size</a></li><li class="chapter-item "><a href="../../posts/rust/implment_file_upload_backend.html"><strong aria-hidden="true">7.15.</strong> impliment file upload</a></li><li class="chapter-item "><a href="../../posts/rust/this_is_add_post_cli_implementation_in_rust.html"><strong aria-hidden="true">7.16.</strong> this is add_post cli implementation in rust</a></li><li class="chapter-item "><a href="../../posts/rust/use_rust_implment_a_copyclipbord_cli.html"><strong aria-hidden="true">7.17.</strong> Use rust implment a copyclipbord CLI</a></li><li class="chapter-item "><a href="../../posts/rust/sqlite_database_add_delete_update_show_in_rust.html"><strong aria-hidden="true">7.18.</strong> sqlite database add delete update show in rust</a></li><li class="chapter-item "><a href="../../posts/rust/implementing_tokio_joinhandle_for_wasm.html"><strong aria-hidden="true">7.19.</strong> Implementing tokio JoinHandle for wasm</a></li><li class="chapter-item "><a href="../../posts/rust/rust_implement_a_crate_for_encode_and_decode_brainfuck_and_ook.html"><strong aria-hidden="true">7.20.</strong> rust implement a crate for encode and decode brainfuck and ook</a></li><li class="chapter-item "><a href="../../posts/rust/slint_builtin_elements.html"><strong aria-hidden="true">7.21.</strong> Slint Builtin Elements</a></li><li class="chapter-item "><a href="../../posts/rust/corporate_network_install_rust_on_windows.html"><strong aria-hidden="true">7.22.</strong> Corporate network install Rust on windows</a></li><li class="chapter-item "><a href="../../posts/rust/rust_binary_file_how_to_judge_static_link_or_dynamic_link_in_macos.html"><strong aria-hidden="true">7.23.</strong> rust binary file how to judge static link or dynamic link in Macos</a></li><li class="chapter-item "><a href="../../posts/rust/rust_binary_include_dir_and_get_contents.html"><strong aria-hidden="true">7.24.</strong> rust binary include dir and get contents</a></li><li class="chapter-item "><a href="../../posts/rust/how_to_create_yolov8_based_object_detection_web_service_using_python,_julia,_node.js,_javascript,_go_and_rust.html"><strong aria-hidden="true">7.25.</strong> How to create YOLOv8-based object detection web service using Python, Julia, Node.js, JavaScript, Go and Rust</a></li><li class="chapter-item "><a href="../../posts/rust/implment_builder_proc_macro_for_command_struct.html"><strong aria-hidden="true">7.26.</strong> implment Builder proc-macro for Command struct</a></li></ol></li><li class="chapter-item "><a href="../../posts/java/java.html"><strong aria-hidden="true">8.</strong> Java</a><a class="toggle"><div>❱</div></a></li><li><ol class="section"><li class="chapter-item "><a href="../../posts/java/java_grammar.html"><strong aria-hidden="true">8.1.</strong> java grammar and codewar</a></li><li class="chapter-item "><a href="../../posts/java/run_jar.html"><strong aria-hidden="true">8.2.</strong> java run .jar</a></li><li class="chapter-item "><a href="../../posts/java/java_pomxml_add_defaultgoal_to_build.html"><strong aria-hidden="true">8.3.</strong> Java pomxml add defaultGoal to build</a></li><li class="chapter-item "><a href="../../posts/java/java_set_mvn_mirror.html"><strong aria-hidden="true">8.4.</strong> Java set mvn mirror</a></li></ol></li><li class="chapter-item "><a href="../../posts/python/python.html"><strong aria-hidden="true">9.</strong> Python</a><a class="toggle"><div>❱</div></a></li><li><ol class="section"><li class="chapter-item "><a href="../../posts/python/convert_pesn.html"><strong aria-hidden="true">9.1.</strong> convert pesn</a></li><li class="chapter-item "><a href="../../posts/python/find_remove_dir.html"><strong aria-hidden="true">9.2.</strong> find and remove dir</a></li><li class="chapter-item "><a href="../../posts/python/timing_message.html"><strong aria-hidden="true">9.3.</strong> wechat send message</a></li><li class="chapter-item "><a href="../../posts/python/use_python_openpyxl_package_read_and_edit_excel_files.html"><strong aria-hidden="true">9.4.</strong> Use python openpyxl package read and edit excel files</a></li><li class="chapter-item "><a href="../../posts/python/sanctum_model_yaml.html"><strong aria-hidden="true">9.5.</strong> sanctum model yaml</a></li><li class="chapter-item "><a href="../../posts/python/how_to_detect_objects_on_images_using_the_yolov8_neural_network.html"><strong aria-hidden="true">9.6.</strong> How to detect objects on images using the YOLOv8 neural network</a></li><li class="chapter-item "><a href="../../posts/python/use_huggingface_model.html"><strong aria-hidden="true">9.7.</strong> use huggingface model</a></li></ol></li><li class="chapter-item expanded "><a href="../../posts/go/go.html" class="active"><strong aria-hidden="true">10.</strong> Go</a></li><li class="chapter-item "><a href="../../posts/javascript/js.html"><strong aria-hidden="true">11.</strong> Javascript</a><a class="toggle"><div>❱</div></a></li><li><ol class="section"><li class="chapter-item "><a href="../../posts/javascript/js_tutorial.html"><strong aria-hidden="true">11.1.</strong> js tutorial</a></li><li class="chapter-item "><a href="../../posts/javascript/js_tutorial_map.html"><strong aria-hidden="true">11.2.</strong> ja map</a></li><li class="chapter-item "><a href="../../posts/javascript/js_tutorial_math.html"><strong aria-hidden="true">11.3.</strong> js math</a></li><li class="chapter-item "><a href="../../posts/javascript/js_tutorial_object.html"><strong aria-hidden="true">11.4.</strong> js object</a></li><li class="chapter-item "><a href="../../posts/javascript/js_tutorial_set.html"><strong aria-hidden="true">11.5.</strong> js set</a></li><li class="chapter-item "><a href="../../posts/javascript/single_thread_and_asynchronous.html"><strong aria-hidden="true">11.6.</strong> single thread and asynchronous</a></li><li class="chapter-item "><a href="../../posts/javascript/this.html"><strong aria-hidden="true">11.7.</strong> js this</a></li><li class="chapter-item "><a href="../../posts/javascript/js_implment_aes.html"><strong aria-hidden="true">11.8.</strong> js implment aes</a></li><li class="chapter-item "><a href="../../posts/javascript/getting_started_with_ajax.html"><strong aria-hidden="true">11.9.</strong> getting started with ajax</a></li><li class="chapter-item "><a href="../../posts/javascript/BinarySearchTree.html"><strong aria-hidden="true">11.10.</strong> binary search tree</a></li><li class="chapter-item "><a href="../../posts/javascript/goole_zx.html"><strong aria-hidden="true">11.11.</strong> goole zx</a></li><li class="chapter-item "><a href="../../posts/javascript/es6.html"><strong aria-hidden="true">11.12.</strong> es6</a></li></ol></li><li class="chapter-item "><a href="../../posts/ruby/ruby.html"><strong aria-hidden="true">12.</strong> Ruby</a><a class="toggle"><div>❱</div></a></li><li><ol class="section"><li class="chapter-item "><a href="../../posts/ruby/rails_setup_env.html"><strong aria-hidden="true">12.1.</strong> ruby on rails setup environment</a></li><li class="chapter-item "><a href="../../posts/ruby/learn_ruby.html"><strong aria-hidden="true">12.2.</strong> learn ruby</a></li><li class="chapter-item "><a href="../../posts/ruby/ruby_note.html"><strong aria-hidden="true">12.3.</strong> Ruby Note</a></li><li class="chapter-item "><a href="../../posts/ruby/setup_ruby_for_ctf.html"><strong aria-hidden="true">12.4.</strong> Setup ruby for CTF</a></li></ol></li><li class="chapter-item "><a href="../../posts/react/react.html"><strong aria-hidden="true">13.</strong> React</a><a class="toggle"><div>❱</div></a></li><li><ol class="section"><li class="chapter-item "><a href="../../posts/react/react_life_cycle.html"><strong aria-hidden="true">13.1.</strong> react life cycle</a></li><li class="chapter-item "><a href="../../posts/react/react_router.html"><strong aria-hidden="true">13.2.</strong> react router</a></li><li class="chapter-item "><a href="../../posts/react/react_this.html"><strong aria-hidden="true">13.3.</strong> react this</a></li><li class="chapter-item "><a href="../../posts/react/react_interviw.html"><strong aria-hidden="true">13.4.</strong> react interview</a></li><li class="chapter-item "><a href="../../posts/react/important_react_interview.html"><strong aria-hidden="true">13.5.</strong> important react interview</a></li><li class="chapter-item "><a href="../../posts/react/react_quick_reference.html"><strong aria-hidden="true">13.6.</strong> react quick reference</a></li><li class="chapter-item "><a href="../../posts/react/redux_quick_reference.html"><strong aria-hidden="true">13.7.</strong> redux quick reference</a></li></ol></li><li class="chapter-item "><a href="../../posts/vue/vue.html"><strong aria-hidden="true">14.</strong> Vue</a><a class="toggle"><div>❱</div></a></li><li><ol class="section"><li class="chapter-item "><a href="../../posts/vue/vue_ajax.html"><strong aria-hidden="true">14.1.</strong> vue ajax</a></li></ol></li><li class="chapter-item "><a href="../../posts/angular/angular.html"><strong aria-hidden="true">15.</strong> Angular</a><a class="toggle"><div>❱</div></a></li><li><ol class="section"><li class="chapter-item "><a href="../../posts/angular/controller_communication.html"><strong aria-hidden="true">15.1.</strong> controller communication</a></li><li class="chapter-item "><a href="../../posts/angular/creating_custom_directives.html"><strong aria-hidden="true">15.2.</strong> creating custom directives</a></li><li class="chapter-item "><a href="../../posts/angular/directive_notes.html"><strong aria-hidden="true">15.3.</strong> directive notes</a></li><li class="chapter-item "><a href="../../posts/angular/directive_communication.html"><strong aria-hidden="true">15.4.</strong> directive communication</a></li><li class="chapter-item "><a href="../../posts/angular/post_params.html"><strong aria-hidden="true">15.5.</strong> post params</a></li><li class="chapter-item "><a href="../../posts/angular/read_json_angular.html"><strong aria-hidden="true">15.6.</strong> read json angular</a></li><li class="chapter-item "><a href="../../posts/angular/same_route_reload.html"><strong aria-hidden="true">15.7.</strong> same route reload</a></li></ol></li><li class="chapter-item "><a href="../../posts/css/css.html"><strong aria-hidden="true">16.</strong> Css</a><a class="toggle"><div>❱</div></a></li><li><ol class="section"><li class="chapter-item "><a href="../../posts/css/use_css_media.html"><strong aria-hidden="true">16.1.</strong> use css media</a></li></ol></li><li class="chapter-item "><a href="../../posts/php/php.html"><strong aria-hidden="true">17.</strong> Php</a><a class="toggle"><div>❱</div></a></li><li><ol class="section"><li class="chapter-item "><a href="../../posts/php/for_php_string_implment_some_extemtion_functions.html"><strong aria-hidden="true">17.1.</strong> for php string implment some extemtion functions</a></li><li class="chapter-item "><a href="../../posts/php/php_cheatsheet.html"><strong aria-hidden="true">17.2.</strong> PHP cheatsheet</a></li></ol></li><li class="chapter-item "><a href="../../posts/windows/windows.html"><strong aria-hidden="true">18.</strong> Windows</a><a class="toggle"><div>❱</div></a></li><li><ol class="section"><li class="chapter-item "><a href="../../posts/windows/windows.html"><strong aria-hidden="true">18.1.</strong> Windows</a></li><li class="chapter-item "><a href="../../posts/windows/windows10_use_powershell_dedup_redundent_path.html"><strong aria-hidden="true">18.2.</strong> Windows10 use PowerShell dedup redundent PATH</a></li></ol></li><li class="chapter-item "><a href="../../posts/leetcode/leetcode.html"><strong aria-hidden="true">19.</strong> Leetcode</a><a class="toggle"><div>❱</div></a></li><li><ol class="section"><li class="chapter-item "><a href="../../posts/leetcode/rust_leetcode.html"><strong aria-hidden="true">19.1.</strong> rust leetcode</a></li><li class="chapter-item "><a href="../../posts/leetcode/rust_codewar.html"><strong aria-hidden="true">19.2.</strong> rust codewar</a></li><li class="chapter-item "><a href="../../posts/leetcode/swift_codewar.html"><strong aria-hidden="true">19.3.</strong> swift codewar</a></li><li class="chapter-item "><a href="../../posts/leetcode/js_leetcode.html"><strong aria-hidden="true">19.4.</strong> js leetcode</a></li><li class="chapter-item "><a href="../../posts/leetcode/java_leetcode.html"><strong aria-hidden="true">19.5.</strong> java leetcode</a></li><li class="chapter-item "><a href="../../posts/leetcode/rust_huawei.html"><strong aria-hidden="true">19.6.</strong> huawei test</a></li><li class="chapter-item "><a href="../../posts/leetcode/rust_utils.html"><strong aria-hidden="true">19.7.</strong> rust common functions</a></li><li class="chapter-item "><a href="../../posts/leetcode/olympiad_training.html"><strong aria-hidden="true">19.8.</strong> Computer olympiad training</a></li></ol></li><li class="chapter-item "><a href="../../posts/ctf/CTF.html"><strong aria-hidden="true">20.</strong> CTF</a><a class="toggle"><div>❱</div></a></li><li><ol class="section"><li class="chapter-item "><a href="../../posts/ctf/CTF_Note.html"><strong aria-hidden="true">20.1.</strong> CTF Note</a></li><li class="chapter-item "><a href="../../posts/ctf/0.1_Web.html"><strong aria-hidden="true">20.2.</strong> Web</a></li><li class="chapter-item "><a href="../../posts/ctf/4.1_Misc.html"><strong aria-hidden="true">20.3.</strong> Misc</a></li><li class="chapter-item "><a href="../../posts/ctf/3.2_PWN_note.html"><strong aria-hidden="true">20.4.</strong> PWN</a></li><li class="chapter-item "><a href="../../posts/ctf/3.1_Crypto.html"><strong aria-hidden="true">20.5.</strong> Crypto</a></li><li class="chapter-item "><a href="../../posts/ctf/3.4_RSA_note.html"><strong aria-hidden="true">20.6.</strong> Rsa attack</a></li><li class="chapter-item "><a href="../../posts/ctf/3.5_Base64.html"><strong aria-hidden="true">20.7.</strong> Base64</a></li><li class="chapter-item "><a href="../../posts/ctf/0.0_SQL Injection Cheatsheet.html"><strong aria-hidden="true">20.8.</strong> SQL Injection Cheatsheet</a></li><li class="chapter-item "><a href="../../posts/ctf/1.1_SQL_injection.html"><strong aria-hidden="true">20.9.</strong> SQL Injection</a></li><li class="chapter-item "><a href="../../posts/ctf/1.2_SQL_injection_UNION_attacks.html"><strong aria-hidden="true">20.10.</strong> SQL Injection UNION attacks</a></li><li class="chapter-item "><a href="../../posts/ctf/1.3_Blind SQL injection.html"><strong aria-hidden="true">20.11.</strong> Blind SQL Injection</a></li><li class="chapter-item "><a href="../../posts/ctf/1.4_Code Injection.html"><strong aria-hidden="true">20.12.</strong> Code Injection</a></li><li class="chapter-item "><a href="../../posts/ctf/1.5_SSRF.html"><strong aria-hidden="true">20.13.</strong> SSRF</a></li><li class="chapter-item "><a href="../../posts/ctf/1.6_OS command injection.html"><strong aria-hidden="true">20.14.</strong> OS command injection</a></li><li class="chapter-item "><a href="../../posts/ctf/1.7_Local file inclusion.html"><strong aria-hidden="true">20.15.</strong> Local file inclusion</a></li><li class="chapter-item "><a href="../../posts/ctf/1.8_Remote file inclusion.html"><strong aria-hidden="true">20.16.</strong> Remote file inclusion</a></li><li class="chapter-item "><a href="../../posts/ctf/1.9_CSRFm.html"><strong aria-hidden="true">20.17.</strong> CSRF</a></li><li class="chapter-item "><a href="../../posts/ctf/1.10_NoSQL injection.html"><strong aria-hidden="true">20.18.</strong> NoSQL injection</a></li><li class="chapter-item "><a href="../../posts/ctf/1.11_JSON injection.html"><strong aria-hidden="true">20.19.</strong> JSON injection</a></li><li class="chapter-item "><a href="../../posts/ctf/1.12_CTF_Web_SQL_Note.html"><strong aria-hidden="true">20.20.</strong> CTF Web SQL Note</a></li><li class="chapter-item "><a href="../../posts/ctf/2.1_XXE.html"><strong aria-hidden="true">20.21.</strong> XXE</a></li><li class="chapter-item "><a href="../../posts/ctf/2.2_XSS.html"><strong aria-hidden="true">20.22.</strong> XSS</a></li><li class="chapter-item "><a href="../../posts/ctf/2.3_Upload File.html"><strong aria-hidden="true">20.23.</strong> Upload File</a></li><li class="chapter-item "><a href="../../posts/ctf/2.4_serialize_unserialize.html"><strong aria-hidden="true">20.24.</strong> serialize unserialize</a></li><li class="chapter-item "><a href="../../posts/ctf/2.5_Race condition.html"><strong aria-hidden="true">20.25.</strong> Race condition</a></li><li class="chapter-item "><a href="../../posts/ctf/zip_plain_text_attack.html"><strong aria-hidden="true">20.26.</strong> Zip plain text attack</a></li><li class="chapter-item "><a href="../../posts/ctf/3.3_pwn HCTF2016 brop.html"><strong aria-hidden="true">20.27.</strong> pwn HCTF2016 brop</a></li><li class="chapter-item "><a href="../../posts/ctf/pwn_patch_defense_skill.html"><strong aria-hidden="true">20.28.</strong> PWN Patch defense skill</a></li><li class="chapter-item "><a href="../../posts/ctf/pwn_stack_overflow.html"><strong aria-hidden="true">20.29.</strong> PWN stack overflow</a></li><li class="chapter-item "><a href="../../posts/ctf/pwn_heap_overflow.html"><strong aria-hidden="true">20.30.</strong> PWN heap overflow</a></li><li class="chapter-item "><a href="../../posts/ctf/pwn_format_string_vulnerability.html"><strong aria-hidden="true">20.31.</strong> PWN Format String Vulnerability</a></li><li class="chapter-item "><a href="../../posts/ctf/kali_linux_tutorials.html"><strong aria-hidden="true">20.32.</strong> Kali linux tutorials</a></li><li class="chapter-item "><a href="../../posts/ctf/google_dorks_2023_lists.html"><strong aria-hidden="true">20.33.</strong> Google Dorks 2023 Lists</a></li><li class="chapter-item "><a href="../../posts/ctf/dvwa_writeup.html"><strong aria-hidden="true">20.34.</strong> DVWA WriteUp</a></li><li class="chapter-item "><a href="../../posts/ctf/bwapp_writeup.html"><strong aria-hidden="true">20.35.</strong> bWAPP WriteUp</a></li><li class="chapter-item "><a href="../../posts/ctf/sqlilabs_writeup.html"><strong aria-hidden="true">20.36.</strong> sqlilabs WriteUp</a></li><li class="chapter-item "><a href="../../posts/ctf/pwnable_kr_challenge.html"><strong aria-hidden="true">20.37.</strong> Solutions for pwnable.kr</a></li><li class="chapter-item "><a href="../../posts/ctf/the_periodic_table.html"><strong aria-hidden="true">20.38.</strong> The Periodic Table</a></li><li class="chapter-item "><a href="../../posts/ctf/pwntools_cheatsheet.html"><strong aria-hidden="true">20.39.</strong> Pwntools Cheatsheet</a></li><li class="chapter-item "><a href="../../posts/ctf/gdb_cheatsheet.html"><strong aria-hidden="true">20.40.</strong> GDB Cheatsheet</a></li></ol></li><li class="chapter-item "><a href="../../posts/iltes/iltes.html"><strong aria-hidden="true">21.</strong> ILTES</a><a class="toggle"><div>❱</div></a></li><li><ol class="section"><li class="chapter-item "><a href="../../posts/iltes/iltes_writing.html"><strong aria-hidden="true">21.1.</strong> ILTES Writing</a></li></ol></li></ol>
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                    <main>
                        <h1 id="go-cheatsheet"><a class="header" href="#go-cheatsheet">Go <em>cheatsheet</em></a></h1>
<h3 id="hello-world"><a class="header" href="#hello-world">Hello world</a></h3>
<h4 id="hellogo"><a class="header" href="#hellogo">hello.go</a></h4>
<pre><code class="language-go">package main

import &quot;fmt&quot;

func main() {
  message := greetMe(&quot;world&quot;)
  fmt.Println(message)
}

func greetMe(name string) string {
  return &quot;Hello, &quot; + name + &quot;!&quot;
}
</code></pre>
<pre><code class="language-sh">$ go build
</code></pre>
<h3 id="variables"><a class="header" href="#variables">Variables</a></h3>
<h4 id="variable-declaration"><a class="header" href="#variable-declaration">Variable declaration</a></h4>
<pre><code class="language-go">var msg string
msg = &quot;Hello&quot;
</code></pre>
<h4 id="shortcut-of-above-infers-type"><a class="header" href="#shortcut-of-above-infers-type">Shortcut of above (Infers type)</a></h4>
<pre><code>msg := &quot;Hello&quot;
</code></pre>
<h3 id="constants"><a class="header" href="#constants">Constants</a></h3>
<pre><code>const Phi = 1.618
</code></pre>
<p>Constants can be character, string, boolean, or numeric values.</p>
<h2 id="basic-types"><a class="header" href="#basic-types">Basic types</a></h2>
<h3 id="strings"><a class="header" href="#strings">Strings</a></h3>
<pre><code class="language-go">str := &quot;Hello&quot;
</code></pre>
<pre><code class="language-go">str := `Multiline
string`
</code></pre>
<p>Strings are of type <code>string</code>.</p>
<h3 id="numbers"><a class="header" href="#numbers">Numbers</a></h3>
<h4 id="typical-types"><a class="header" href="#typical-types">Typical types</a></h4>
<pre><code class="language-go">num := 3          // int
num := 3.         // float64
num := 3 + 4i     // complex128
num := byte('a')  // byte (alias for uint8)
</code></pre>
<h4 id="other-types"><a class="header" href="#other-types">Other types</a></h4>
<pre><code class="language-go">var u uint = 7        // uint (unsigned)
var p float32 = 22.7  // 32-bit float
</code></pre>
<h3 id="arrays"><a class="header" href="#arrays">Arrays</a></h3>
<pre><code class="language-go">// var numbers [5]int
numbers := [...]int{0, 0, 0, 0, 0}
</code></pre>
<p>Arrays have a fixed size.</p>
<h3 id="slices"><a class="header" href="#slices">Slices</a></h3>
<pre><code class="language-go">slice := []int{2, 3, 4}
</code></pre>
<pre><code class="language-go">slice := []byte(&quot;Hello&quot;)
</code></pre>
<p>Slices have a dynamic size, unlike arrays.</p>
<h3 id="pointers"><a class="header" href="#pointers">Pointers</a></h3>
<pre><code class="language-go">func main () {
  b := *getPointer()
  fmt.Println(&quot;Value is&quot;, b)
}

 
</code></pre>
<pre><code class="language-go">func getPointer () (myPointer *int) {
  a := 234
  return &amp;a
}

 
</code></pre>
<pre><code class="language-go">a := new(int)
*a = 234

 
</code></pre>
<p>Pointers point to a memory location of a variable. Go is fully garbage-collected.</p>
<h3 id="type-conversions"><a class="header" href="#type-conversions">Type conversions</a></h3>
<pre><code class="language-go">i := 2
f := float64(i)
u := uint(i)
</code></pre>
<h2 id="flow-control"><a class="header" href="#flow-control">Flow control</a></h2>
<h3 id="conditional"><a class="header" href="#conditional">Conditional</a></h3>
<pre><code class="language-go">if day == &quot;sunday&quot; || day == &quot;saturday&quot; {
  rest()
} else if day == &quot;monday&quot; &amp;&amp; isTired() {
  groan()
} else {
  work()
}

</code></pre>
<h3 id="statements-in-if"><a class="header" href="#statements-in-if">Statements in if</a></h3>
<pre><code class="language-go">if _, err := doThing(); err != nil {
  fmt.Println(&quot;Uh oh&quot;)
}

 
</code></pre>
<p>A condition in an <code>if</code> statement can be preceded with a statement before a <code>;</code>. Variables declared by the statement are only in scope until the end of the <code>if</code>.</p>
<h3 id="switch"><a class="header" href="#switch">Switch</a></h3>
<pre><code class="language-go">switch day {
  case &quot;sunday&quot;:
    // cases don't &quot;fall through&quot; by default!
    fallthrough

  case &quot;saturday&quot;:
    rest()

  default:
    work()
}
</code></pre>
<p>See: <a href="https://github.com/golang/go/wiki/Switch">Switch</a></p>
<h3 id="for-loop"><a class="header" href="#for-loop">For loop</a></h3>
<pre><code class="language-go">for count := 0; count &lt;= 10; count++ {
  fmt.Println(&quot;My counter is at&quot;, count)
}
</code></pre>
<h3 id="for-range-loop"><a class="header" href="#for-range-loop">For-Range loop</a></h3>
<pre><code class="language-go">entry := []string{&quot;Jack&quot;,&quot;John&quot;,&quot;Jones&quot;}
for i, val := range entry {
  fmt.Printf(&quot;At position %d, the character %s is present\n&quot;, i, val)
}
</code></pre>
<p>See: <a href="https://gobyexample.com/range">For-Range loops</a></p>
<h3 id="while-loop"><a class="header" href="#while-loop">While loop</a></h3>
<pre><code class="language-go">n := 0
x := 42
for n != x {
  n := guess()
}
</code></pre>
<h2 id="functions"><a class="header" href="#functions">Functions</a></h2>
<h3 id="lambdas"><a class="header" href="#lambdas">Lambdas</a></h3>
<pre><code class="language-go">myfunc := func() bool {
  return x &gt; 10000
}
</code></pre>
<p>Functions are first class objects.</p>
<h3 id="multiple-return-types"><a class="header" href="#multiple-return-types">Multiple return types</a></h3>
<pre><code class="language-go">a, b := getMessage()
</code></pre>
<pre><code class="language-go">func getMessage() (a string, b string) {
  return &quot;Hello&quot;, &quot;World&quot;
}

 
</code></pre>
<h3 id="named-return-values"><a class="header" href="#named-return-values">Named return values</a></h3>
<pre><code class="language-go">func split(sum int) (x, y int) {
  x = sum * 4 / 9
  y = sum - x
  return
}

 
</code></pre>
<p>By defining the return value names in the signature, a <code>return</code> (no args) will return variables with those names.</p>
<h2 id="packages"><a class="header" href="#packages">Packages</a></h2>
<h3 id="importing"><a class="header" href="#importing">Importing</a></h3>
<pre><code class="language-go">import &quot;fmt&quot;
import &quot;math/rand&quot;
</code></pre>
<pre><code class="language-go">import (
  &quot;fmt&quot;        // gives fmt.Println
  &quot;math/rand&quot;  // gives rand.Intn
)
</code></pre>
<p>Both are the same.</p>
<h3 id="aliases"><a class="header" href="#aliases">Aliases</a></h3>
<pre><code class="language-go">import r &quot;math/rand&quot;

 
</code></pre>
<pre><code class="language-go">r.Intn()
</code></pre>
<h3 id="exporting-names"><a class="header" href="#exporting-names">Exporting names</a></h3>
<pre><code class="language-go">func Hello () {
  ···
}
</code></pre>
<p>Exported names begin with capital letters.</p>
<h3 id="packages-1"><a class="header" href="#packages-1">Packages</a></h3>
<pre><code class="language-go">package hello
</code></pre>
<p>Every package file has to start with <code>package</code>.</p>
<h2 id="concurrency"><a class="header" href="#concurrency">Concurrency</a></h2>
<h3 id="goroutines"><a class="header" href="#goroutines">Goroutines</a></h3>
<pre><code class="language-go">func main() {
  // A &quot;channel&quot;
  ch := make(chan string)

  // Start concurrent routines
  go push(&quot;Moe&quot;, ch)
  go push(&quot;Larry&quot;, ch)
  go push(&quot;Curly&quot;, ch)

  // Read 3 results
  // (Since our goroutines are concurrent,
  // the order isn't guaranteed!)
  fmt.Println(&lt;-ch, &lt;-ch, &lt;-ch)
}

</code></pre>
<pre><code class="language-go">func push(name string, ch chan string) {
  msg := &quot;Hey, &quot; + name
  ch &lt;- msg
}

 
</code></pre>
<p>Channels are concurrency-safe communication objects, used in goroutines.</p>
<h3 id="buffered-channels"><a class="header" href="#buffered-channels">Buffered channels</a></h3>
<pre><code class="language-go">ch := make(chan int, 2)
ch &lt;- 1
ch &lt;- 2
ch &lt;- 3
// fatal error:
// all goroutines are asleep - deadlock!

 
</code></pre>
<p>Buffered channels limit the amount of messages it can keep.</p>
<h3 id="closing-channels"><a class="header" href="#closing-channels">Closing channels</a></h3>
<h4 id="closes-a-channel"><a class="header" href="#closes-a-channel">Closes a channel</a></h4>
<pre><code class="language-go">ch &lt;- 1
ch &lt;- 2
ch &lt;- 3
close(ch)

 
</code></pre>
<h4 id="iterates-across-a-channel-until-its-closed"><a class="header" href="#iterates-across-a-channel-until-its-closed">Iterates across a channel until its closed</a></h4>
<pre><code class="language-go">for i := range ch {
  ···
}

 
</code></pre>
<h4 id="closed-if-ok--false"><a class="header" href="#closed-if-ok--false">Closed if <code>ok == false</code></a></h4>
<pre><code class="language-go">v, ok := &lt;- ch
</code></pre>
<h3 id="waitgroup"><a class="header" href="#waitgroup">WaitGroup</a></h3>
<pre><code class="language-go">import &quot;sync&quot;

func main() {
  var wg sync.WaitGroup
  
  for _, item := range itemList {
    // Increment WaitGroup Counter
    wg.Add(1)
    go doOperation(&amp;wg, item)
  }
  // Wait for goroutines to finish
  wg.Wait()
  
}

</code></pre>
<pre><code class="language-go">func doOperation(wg *sync.WaitGroup, item string) {
  defer wg.Done()
  // do operation on item
  // ...
}

 
</code></pre>
<p>A WaitGroup waits for a collection of goroutines to finish. The main goroutine calls Add to set the number of goroutines to wait for. The goroutine calls <code>wg.Done()</code> when it finishes.</p>
<h2 id="error-control"><a class="header" href="#error-control">Error control</a></h2>
<h3 id="defer"><a class="header" href="#defer">Defer</a></h3>
<pre><code class="language-go">func main() {
  defer fmt.Println(&quot;Done&quot;)
  fmt.Println(&quot;Working...&quot;)
}

 
</code></pre>
<p>Defers running a function until the surrounding function returns. The arguments are evaluated immediately, but the function call is not ran until later.</p>
<h3 id="deferring-functions"><a class="header" href="#deferring-functions">Deferring functions</a></h3>
<pre><code class="language-go">func main() {
  defer func() {
    fmt.Println(&quot;Done&quot;)
  }()
  fmt.Println(&quot;Working...&quot;)
}
 
</code></pre>
<p>Lambdas are better suited for defer blocks.</p>
<pre><code class="language-go">func main() {
  var d = int64(0)
  defer func(d *int64) {
    fmt.Printf(&quot;&amp; %v Unix Sec\n&quot;, *d)
  }(&amp;d)
  fmt.Print(&quot;Done &quot;)
  d = time.Now().Unix()
}

 

 

 
</code></pre>
<p>The defer func uses current value of d, unless we use a pointer to get final value at end of main.</p>
<h2 id="structs"><a class="header" href="#structs">Structs</a></h2>
<h3 id="defining"><a class="header" href="#defining">Defining</a></h3>
<pre><code class="language-go">type Vertex struct {
  X int
  Y int
}
</code></pre>
<pre><code class="language-go">func main() {
  v := Vertex{1, 2}
  v.X = 4
  fmt.Println(v.X, v.Y)
}
</code></pre>
<h3 id="literals"><a class="header" href="#literals">Literals</a></h3>
<pre><code class="language-go">v := Vertex{X: 1, Y: 2}
</code></pre>
<pre><code class="language-go">// Field names can be omitted
v := Vertex{1, 2}
</code></pre>
<pre><code class="language-go">// Y is implicit
v := Vertex{X: 1}
</code></pre>
<p>You can also put field names.</p>
<h3 id="pointers-to-structs"><a class="header" href="#pointers-to-structs">Pointers to structs</a></h3>
<pre><code class="language-go">v := &amp;Vertex{1, 2}
v.X = 2
</code></pre>
<p>Doing <code>v.X</code> is the same as doing <code>(*v).X</code>, when <code>v</code> is a pointer.</p>
<h2 id="methods"><a class="header" href="#methods">Methods</a></h2>
<h3 id="receivers"><a class="header" href="#receivers">Receivers</a></h3>
<pre><code class="language-go">type Vertex struct {
  X, Y float64
}
</code></pre>
<pre><code class="language-go">func (v Vertex) Abs() float64 {
  return math.Sqrt(v.X * v.X + v.Y * v.Y)
}

 
</code></pre>
<pre><code class="language-go">v := Vertex{1, 2}
v.Abs()
</code></pre>
<p>There are no classes, but you can define functions with <em>receivers</em>.</p>
<h3 id="mutation"><a class="header" href="#mutation">Mutation</a></h3>
<pre><code class="language-go">func (v *Vertex) Scale(f float64) {
  v.X = v.X * f
  v.Y = v.Y * f
}

 
</code></pre>
<pre><code class="language-go">v := Vertex{6, 12}
v.Scale(0.5)
// `v` is updated
</code></pre>
<p>By defining your receiver as a pointer (<code>*Vertex</code>), you can do mutations.</p>
<h2 id="interfaces"><a class="header" href="#interfaces">Interfaces</a></h2>
<h3 id="a-basic-interface"><a class="header" href="#a-basic-interface">A basic interface</a></h3>
<pre><code class="language-go">type Shape interface {
  Area() float64
  Perimeter() float64
}
</code></pre>
<h3 id="struct"><a class="header" href="#struct">Struct</a></h3>
<pre><code class="language-go">
type Rectangle struct {
  Length, Width float64
}
</code></pre>
<p>Struct <code>Rectangle</code> implicitly implements interface <code>Shape</code> by implementing all of its methods.</p>
<h3 id="methods-1"><a class="header" href="#methods-1">Methods</a></h3>
<pre><code class="language-go">
func (r Rectangle) Area() float64 {
  return r.Length * r.Width
}

func (r Rectangle) Perimeter() float64 {
  return 2 * (r.Length + r.Width)
}
</code></pre>
<p>The methods defined in <code>Shape</code> are implemented in <code>Rectangle</code>.</p>
<h3 id="interface-example"><a class="header" href="#interface-example">Interface example</a></h3>
<pre><code class="language-go">
func main() {
  var r Shape = Rectangle{Length: 3, Width: 4}
  fmt.Printf(&quot;Type of r: %T, Area: %v, Perimeter: %v.&quot;, r, r.Area(), r.Perimeter())
}
</code></pre>
<h2 id="references"><a class="header" href="#references">References</a></h2>
<h3 id="official-resources"><a class="header" href="#official-resources">Official resources</a></h3>
<ul>
<li><a href="https://tour.golang.org/welcome/1">A tour of Go</a> <em>(tour.golang.org)</em></li>
<li><a href="https://github.com/golang/go/wiki/">Golang wiki</a> <em>(github.com)</em></li>
<li><a href="https://golang.org/doc/effective_go.html">Effective Go</a> <em>(golang.org)</em></li>
</ul>
<h3 id="other-links"><a class="header" href="#other-links">Other links</a></h3>
<ul>
<li><a href="https://gobyexample.com/">Go by Example</a> <em>(gobyexample.com)</em></li>
<li><a href="https://awesome-go.com/">Awesome Go</a> <em>(awesome-go.com)</em></li>
<li><a href="https://www.youtube.com/channel/UC_BzFbxG2za3bp5NRRRXJSw">JustForFunc Youtube</a> <em>(youtube.com)</em></li>
<li><a href="https://github.com/golang/go/wiki/CodeReviewComments">Style Guide</a> <em>(github.com)</em></li>
</ul>

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